Nuclear Ribosomal ITS Research Articles

Morphological and molecular characterization of Paragonimus caliensis Little, 1968 (Trematoda: Paragonimidae) from Medellin and Pichinde, Colombia

Paragonimiasis is a subacute to chronic inflammatory granulomatous lung disease caused by the genus Paragonimus. In Latin America Paragonimus mexicanus Miyazaki & Ishii, 1968 is the only confirmed species to cause human infections. Paragonimus caliensis Little, 1968 is an uncommon species often regarded as a synonym of P. mexicanus. Recently, the study of two types of Paragonimus metacercariae from Costa Rica has provided new molecular and morphological evidence that P. caliensis is a separate species from P. mexicanus. In the present study, molecular, morphological and phylogenetic tools have been used to characterize two populations of Paragonimus located at west of Medellin, Antioquia and at Pichinde, Valle del Cauca (type locality of P. caliensis), Colombia. Adults and metacercariae obtained from Medellin, and metacercariae from Pichinde were analyzed. For morphological observations we used light microscopy and scanning electron microscopy (SEM). Morphology of metacercariae and adults matched with the holotype of P. caliensis. The number and arrangement of sensory papillae in the acetabulum region differs from the morphotypes reported for P. caliensis in Costa Rica. Two morphotypes in branching patterns of ovary and two morphotypes in branching patterns of testes were identified. The main morphological differences between P. caliensis and P. mexicanus corresponded to the size of gonads and their relative positions in the body, and the occasional presence of a cyst wall in P. caliensis metacercariae. The molecular and phylogenetic analyses (using nuclear ribosomal ITS2 and partial cytochrome c oxidase subunit 1 CO1 sequences) confirmed that P. caliensis from the type locality is the same species from Medellin and Costa Rica. Furthermore, these analyses also suggest genetic as well as geographical separation of P. caliensis populations between Colombia and Costa Rica. Currently, P. mexicanus and P. caliensis are sympatric in the Colombian Pacific bioregion, and specific diagnosis based on their egg size is not possible. Therefore, it is necessary to determine the biogeographic distribution ranges of both species and to implement molecular techniques to establish the role of P. caliensis in human paragonimiasis in Colombia.

Occurrence of Diplodia corticola, including new oak host records, in Wisconsin, USA

SummaryIn the United States, diseased oaks (Quercus species) exhibit tip blight, branch and stem cankers, and dieback often attributed to Diplodia species or related fungi. Emergence of Diplodia corticola as a pathogen of European oaks, and reports of this fungus in the eastern and western United States, prompted re‐examination of strains from Wisconsin. These had been obtained in the late 1990s and early 2000s and previously identified only as Diplodia species. Nuclear ribosomal ITS sequences were obtained from the Wisconsin strains and analysed with other sequences from GenBank. Wisconsin strains confirmed as D. corticola were from northern red oak (Q. rubra), black oak (Q. velutina), white oak (Q. alba) and bur oak (Q. macrocarpa). Other strains from oaks in Wisconsin were D. mutila and D. seriata. Wound inoculation of northern red, white and bur oak seedlings with D. corticola in a greenhouse resulted in shoot death and stem lesions, from which the pathogen was reisolated. We conclude that D. corticola has been present in the northcentral United States for at least two decades and report two previously unrecognized hosts of this pathogen: white oak and bur oak. The roles of D. corticola, related fungi and influences of other environmental factors in deterioration of oak health in North America merit additional investigation.

Pleione jinhuana (Arethuseae; Epidendroideae; Orchidaceae), a new species from China based on morphological and DNA evidence

Pleione jinhuana, a new orchid from China, is illustrated and described based on morphological and phylogenetic evidence. Detailed morphological comparisons between the new species and other members of Pleione indicate that P. jinhuana is similar to P. bulbocodioides and P. formosana but differs in having a lip with an erose apical margin and lateral lobes not enfolding the column. To explore the phylogenetic position of this species, nuclear ribosomal ITS and plastid DNA (matK exon, trnT-trnL spacer, trnL exon and trnL-trnF spacer) were sequenced for P. jinhuana and individuals of P. formosana collected in Taiwan, Fujian and Zhejiang Provinces. The morphological and molecular evidence support the hypothesis that P. jinhuana is a new species.

Cymbidium densiflorum (Orchidaceae; Epidendroideae; Cymbidieae): a new orchid species from China based on morphological and molecular evidence

A new orchid species, Cymbidium densiflorum, from Yunnan, China, is described and illustrated here based on morphological and molecular analyses. A detailed comparison between the newly discovered orchid and other members of Cymbidium was conducted. The new plant belongs to C. section Cymbidium and has a pendent inflorescence, thick-coriaceous flowers with two pollinia and rigid leaves, and it differs greatly from all other known species of this section by being a large plant bearing leaves with an acute, oblique apex and producing a long inflorescence with more than 30 purplish brown large flowers, in which the lateral sepals are oblique and narrowly elliptic with a tooth at the apex and narrowly ovate-elliptic petals. A molecular study based on the nuclear ribosomal ITS and plastid matK, rbcL, trnG, trnL and atpI DNA sequence data indicated that C. densiflorum is sister to C. paucifolium.

Phylogeny and Evolution of the Neotropical Radiation of Lachemilla (Rosaceae): Uncovering a History of Reticulate Evolution and Implications for Infrageneric Classification

Reticulate evolution often leads to incongruence between nuclear and plastid phylogenies, and comparisons between them have been used as a first approximation to disentangle patterns of hybridization. Because other processes like incomplete lineage sorting and phylogenetic error also produce similar incongruence patterns, additional sources of evidence must be incorporated. Here we focus on reconstructing the phylogeny of Lachemilla (Rosaceae) using nuclear ribosomal ITS and plastid trnL-FDNAsequences, and explore widespread patterns of cytonuclear discordance in this group. Lachemilla is a highly morphologically variable group of perennial herbs and shrubs, and a nearly ubiquitous member of the diverse Neotropical high-altitude grasslands. Our analyses identified four major clades within Lachemilla that are in part congruent with previous morphological classifications of the group. Furthermore, using multiple sources of evidence, including a procrustean approach to cophylogeny estimation, coalescent-based simulations, phylogenetic networks, chromosome counts, and genome size estimations, we also revealed a large-scale pattern of incongruence between the plastid and nuclear phylogenies in Lachemilla, which is mainly the result of widespread hybridization and polyploidy.We also estimated that the origin of Lachemilla in South America (;14.5 MYA) predates the “rapid-uplift” diversification model that has been suggested for other high species-richness Andean plant clades, but following the formation of the high-elevation Andean grasslands during the last 5 MYA, a rapid accumulation of particular nested lineages has contributed to the ubiquitous presence of Lachemilla in these biomes.

Platanthera guangdongensis and P. zijinensis (Orchidaceae: Orchideae), two new species from China: Evidence from morphological and molecular analyses<br />

Two new Platanthera (Orchidinae, Orchideae, Orchidoideae) species, P. guangdongensis and P. zijinensis, from the Guangdong Province in China are described and illustrated based on morphological and molecular analyses. Platanthera guangdongensis is leafless and resembles P. fujianensis, but it differs in terms of the shorter and/or smaller inflorescence, floral bract, dorsal sepal, lateral sepal, petal, and ligulate lip. Platanthera zijinensis is morphologically similar to P. minor, but it differs by the ovate-oblong to ovate floral bract, colour of flower, ovate dorsal sepal, oblong lateral sepal, ovate-oblong lip, and curved forward spur. The phylogenetic analyses based on nuclear ribosomal ITS and chloroplast (rbcL and matK) sequence data support that P. zijinensis and P. guangdongensis being sisters to each other and genetically sister to P. minor. The chloroplast rbcL of P. guangdongensis is a pseudogene, supporting its characterization as a holomycotrophic orchid.

Three new species of Fomitiporella (Hymenochaetales, Basidiomycota) based on the evidence from morphology and DNA sequence data.

Fomitiporella austroasiana, F. mangrovei and F. vietnamensis are described and illustrated as new species based on morphological characters and molecular evidence. They have annual to perennial, mostly resupinate basidiomata with grayish fresh pores, an indistinct subiculum, lack any kind of setae, have brownish, thick-walled basidiospores, and cause a white rot. The distinctive morphological characters of the new species and their related species are discussed. Phylogenies based on the nuclear ribosomal large subunit (28S) and the nuclear ribosomal ITS region show that these three new species form three distinct lineages in the Fomitiporella clade. A key to known species of Fomitiporella is given.

Phylogenetic relationship of Clauseneae (Rutaceae) inferred from plastid and nuclear DNA data and taxonomic implication for some major taxa

Using sequences of the nuclear ribosomal ITS region as well as the chloroplast DNA trnL‐trnF and atpB‐rbcL regions, this study aims to provide further insight into the phylogenetic relationships within Clauseneae and its relationship to Citreae (Rutaceae). Using maximum likelihood (ML) and Bayesian inference (BI), we reconstructed the phylogeny of Clauseneae based on trnL‐F, atpB‐rbcL and ITS sequences. Our data matrix contained 91 accessions, representing 72 species and varieties from 31 genera and two outgroups, including new and extensive sampling of species and varieties representing four genera in the tribe Clauseneae. In the subfamily Aurantioideae, six major clades were resolved with strong support: 1) Micromelum clade: Micromelum; 2) Glycosmis clade: Glycosmis; 3) Bergera clade: Murraya sect. Bergera; 4) Clausena clade: Clausena; 5) Murraya clade: Murraya sect. Murraya + Merrillia; 6) Citreae clade: Citreae. Micromelum, Glycosmis, Clausena and Merrillia were confirmed as monophyletic. In contrast, Murraya s.l. was reconstructed as polyphyletic. Murraya sect. Bergera clustered with Clausena while Murraya sect. Murraya and Merrillia together formed a clade that is sister to the tribe Citreae. All members from Citreae were clustered into a natural group. The genus Micromelum was found to be primitive in this subfamily and more close to Glycosmis. Based on the phylogeny and morphological characters, we discuss the taxonomy of some members of Clauseneae and conclude that the current tribal and generic classification need further revision.

Phylogenetic relationships and generic reassessment of Proustia and allies (Compositae: Nassauvieae)

AbstractProustia is a small southern Andean genus of shrubs, vines and small trees, which are characteristic elements of Chilean and Argentine Andean forests, thickets and desert scrubs. Since Proustia possesses an unusual and characteristic morphology within the Nassauvieae, its circumscription as well as its phylogenetic placement is decisive in understanding the evolution of the tribe. Berylsimpsonia, from the Caribbean, was segregated from Proustia, which currently only includes three species. Lophopappus, another Andean genus, has been closely related to Proustia in sharing style and corolla features that are unusual in the Nassauvieae. The purpose of this work is to evaluate the placement of Proustia within the Nassauvieae, its relationships with Berylsimpsonia and Lophopappus, and the relationships of its species using molecular data and phylogenetic methods. This is the first comprehensive analysis of Proustia. We have included in our study the three currently accepted species of Proustia and seven of its ten infraspecific taxa. For each taxon of Proustia, one to seven accessions were analyzed. Species of Lophopappus and Berylsimpsonia, as well as 16 species belonging to 13 genera of Nassauvieae were also analyzed. We sequenced the nuclear ribosomal ITS and ETS, and the plastid regions ndhF, 5’ trnK–matK, trnL–trnF, and trnL(UAG)–rpl32. Unlike other previous studies, Proustia is not sister to the rest but nested in the tribe in our analyses. Berylsimpsonia vanillosma and P. ilicifolia are distantly related to P. pyrifolia, the type of the genus. According to nuclear DNA data, the infraspecific taxa of P. cuneifolia were recovered all in a well–supported clade, although based on the plastid data P. pyrifolia does not form a lineage separate from P. cuneifolia. Lophopappus is the genus most closely related to Proustia. Regarding the evolution of styles, our results suggest multiple origins of atypical stylar features in the Nassauvieae. As a result of our analyses we propose the segregation of Proustia ilicifolia into the new genus Spinoliva. Morphological data are consistent with the segregation of Proustia and Lophopappus as separate genera. Two species of Proustia, P. cuneifolia and P. pyrifolia are recognized. Three lectotypifications, one neotypification, two new combinations and five rank changes are proposed.

Aphyllophoroid fungi in insular woodlands of eastern Ukraine.

BackgroundFungi play crucial roles in ecosystems and are among the species-richest organism groups on Earth. However, knowledge on their occurrence lags behind the data for animals and plants. Recent analyses of fungal occurrence data from Western, Central and Northern Europe provided important insights into response of fungi to global warming. The consequences of the global changes for biodiversity on a larger geographical scale are not yet understood. Landscapes of Eastern Europe and particularly of eastern Ukraine, with their specific geological history, vegetation and climate, can add substantially new information about fungal diversity in Europe.New informationWe describe the dataset and provide a checklist of aphyllophoroid fungi (non-gilled macroscopic Basidiomycota) from eastern Ukraine sampled in 16 areas between 2007 and 2011. The dataset was managed on the PlutoF biodiversity workbench (http://dx.doi.org/10.15156/BIO/587471) and can also be accessed via Global Biodiversity Information Facility (GBIF, parts of datasets https://doi.org/10.15468/kuspj6 and https://doi.org/10.15468/h7qtfd). This dataset includes 3418 occurences, namely 2727 specimens and 691 observations of fructifications belonging to 349 species of fungi. With these data, the digitised CWU herbarium (V. N. Karazin Kharkiv National University, Ukraine) doubled in size A most detailed description of the substrate's properties and habitat for each record is provided. The specimen records are supplemented by 26 nuclear ribosomal DNA ITS sequences and six 28S sequences. Additionally, 287 photographs depicting diagnostic macro- and microscopic features of fungal fruitbodies as well as studied habitats are linked to the dataset. Most of the specimens have at least one mention in literature and relevant references are displayed as associated with specimen data. In total, 16 publication references are linked to the dataset. The dataset sheds new light on the fungal diversity of Eastern Europe. It is expected to complement other public sources of fungal occurrence information on continental and global levels in addressing macroecological and biogeographical questions.

Phytolacca exiensis, a new species of Phytolaccaceae from west of Hubei province, China

Phytolacca exiensis, a new species of Phytolacca which was discovered from west of Hubei province, China, is discribed and illustrated in this paper. The placement of this new species is accessed based on molecular phylogenetic analysis of the nuclear ribosomal ITS and one chloroplast regions (psbA-trnH) sequences together with mophorlogical comparison. This new species can be easily distinguished from other related species by its carpers connate and plants dioecious.

PRP8 intein in dermatophytes: Evolution and species identification.

Dermatophytes are keratinophilic fungi belonging to the family Arthrodermataceae. Despite having a monophyletic origin, its systematics has always been complex and controversial. Sequencing of nuclear ribosomal ITS and D1/D2 rDNA has been proposed as an efficient tool for identifying species in this group of fungi, while multilocus analyses have been used for phylogenetic species recognition. However, the search for new markers, with sequence and size variation, which enable species identification in only one polymerase chain reaction (PCR) step, is very attractive. Inteins seems to fulfill these characteristics. They are self-splicing genetic elements present within housekeeping coding genes, such as PRP8, that codify the most important protein of the spliceosome. The PRP8 intein has been described for Microsporum canis in databases but has not been studied in dermatophytes in any other published work. Thus, our aim was to determine the potential of this intervening element for establishing phylogenetic relationships among dermatophytes and for identifying species. It was found that all studied species have a full-length PRP8 intein with a Homing Endonuclease belonging to the family LAGLIDADG. Phylogenetic analyses were consistent with other previous phylogenies, confirming Epidermophyton floccosum in the same clade of the Arthroderma gypseum complex, Microsporum audouinii close to M. canis, differentiating A. gypseum from Arthroderma incurvatum, and in addition, better defining the Trichophyton interdigitale and Trichophyton rubrum species grouping. Length polymorphism in the HE region enables identification of the most relevant Microsporum species by a simple PCR-electrophoresis assay. Intein PRP8 within dermatophytes is a powerful additional tool for identifying and systematizing dermatophytes.

Thiersianthus (Marchantiophyta: Lejeuneaceae), a new genus from lowland rainforests in Borneo

The tropical lowland rainforest is a paradise for Lejeuneaceae. Borneo is located in the heart of the biodiversity hotspots of Philippines, Sundaland and Wallacea. During an expedition to explore liverwort diversity of Sabah, Borneo we found an undescribed ocellate taxon in the lowland ultramafic rainforests. Our phylogenetic analyses based on the nuclear ribosomal ITS region and two chloroplast regions (rbcL, trnL-trnF) suggest that this unknown species belongs to the subtribe Lepidolejeuneinae of Lejeuneaceae. On the basis of the combined molecular phylogenetic and morphological data, here we propose a new genus, Thiersianthus, to accommodate this new species. Capillolejeunea known only from the East African Islands and Kymatolejeunea endemic to New Zealand were included in molecular analysis for the first time.

Molecular phylogeny of Scutellaria (Lamiaceae; Scutellarioideae) in Iranian highlands inferred from nrITS and trnL-F sequences

Scutellaria with about 360 species is one of the largest genera of Lamiaceae. The Iranian highlands accommodate about 40 Scutellaria spp., and is considered as one of the main centers of diversity of the genus. Here, we present a phylogenetic study for 44 species of Scutellaria especially from Iranian highlands, representing major subgeneric taxa, based on nuclear ribosomal ITS and trnL intron and trnL-F intergenic spacer using Maximum Parsimony (MP) and Bayesian Inference (BI) analyses. The monophyly of Scutellaria is confirmed in our study, but Scutellaria subg. Scutellaria is shown to be paraphyletic with S. subg. Apeltanthus embedded within it. Moreover, our results reveal that S. subg. Apeltanthus is paraphyletic including one accession of S. repens of S. subg. Scutellaria nested within. In addition, the two sections of S. subg. Apeltanthus, i.e. sect. Apeltanthus and sect. Lupulinaria, are not supported as monophyletic by our plastid and nuclear topologies. Thus, the subgeneric classification of Scutellaria which is mainly based on morphological characters such as the type of inflorescence, shape of calyces, presence of a scutellum and a bladder-like appendage on the upper calyx lip is not supported by our molecular data. Additionally, our phylogenetic study corroborates Paton’s finding on primitive position of S. sect. Scutellaria, but disagrees with the intermediate position of S. sect. Salviifolia between S. subg. Scutellaria and S. subg. Apeltanthus.

Genetic variability of Eurasian Nuphar species unravels possible routes in which freshwater plants could fill their wide areas

Possible routes in which aquatic plants have spreaded across their vast ranges from ancestral areas and refugia still remain poorly known. We have chosen Eurasian yellow water-lilies (Nuphar Sm. sect. Nuphar, Nymphaeaceae) as a model group for a wide-scale phylogeographical study as they represent a common component of the continental freshwater flora. To elucidate the history of diversification of the section Nuphar, we sequenced nuclear ribosomal ITS and chloroplast intergenic spacers (trnH-psbA, trnL–trnF) from 117 localities from almost all the section area. Sequence data were analysed with a statistical parsimony approach using the network algorithm. We also incorporated data on morphological variation and pollen viability. The section Nuphar originated and diversified into several evolutionary lineages in Eastern Asia. Two lineages, represented by N. pumila and N. lutea, spread from the Russian Far East westwards to Siberia and further to Europe. Nuphar pumila also migrated from the Far East to North America (where it is referred to as N. microphylla). Nuphar lutea colonized deglaciated north-eastern Europe not only from the south, but also from the Siberian refugia. Nuphar lutea and N. pumila hybridize rarely in Eastern Europe and Asia and warrant species status. We provide the first evidence, based on a phylogeographical approach, for the origin and diversification of aquatic flowering plants in Eastern Asia. Our results indicate that phylogeographic analysis on the area-wide scale is one of the most efficient ways to deduce possible routes in which aquatic plants have spread across their total range from ancestral areas and refugia.

Heterochromatic and cytomolecular diversification in the Caesalpinia group (Leguminosae): Relationships between phylogenetic and cytogeographical data

The pantropical Caesalpinia group comprises 27 genera and approximately 205 species. The Neotropical species of the group are distributed in three main centers of diversity: the Andes, Mesoamerica (including Mexico, Central America, the southern USA and the Caribbean), and Northeastern Brazil. Our study investigates patterns of phylogenetic, environmental and geographical variation in an attempt to explain the karyotypic diversity which occurs within the Caesalpinia group. Cytogenetic analyses were based on chromosome number and morphology, CMA and DAPI heterochromatic bands, distribution of rDNA sites, and their molecular phylogenetic relationships based on the plastid markers matK, rps16, trnDT, trnL and ycf6 and the nuclear ribosomal marker ITS. Ecological differentiation among cytotypes was tested by comparing sets of climatic variables. In total, twenty species from ten genera of the Caesalpinia group were analysed, and all of them were found to have the same chromosome number (2n=24). CMA+/DAPI− bands were observed on the short arms of the acrocentric chromosomes in all of the species. Additionally, three different patterns were observed on the metacentric chromosomes: proximal CMA+/DAPI− bands, proximal CMA0/DAPI− bands and terminal CMA+/DAPI− bands. The 45S rDNA sites varied from eight to 14, always co-localizing with CMA+/DAPI− bands of acrocentrics, while 5S rDNA was localized in only a single chromosome pair in most species. A correlation between heterochromatic patterns and the geographic distributions/ecological niche of species was observed. Our analyses support some shared effects of the environment, when integrated with phylogeny and geography, on the CMA/DAPI variability. Thus, CMA+ heterochromatin is highly dynamic and its amplification/deamplification might be non-random, generating similar karyotypes in species which are not sister taxa in the molecular phylogeny but which co-occur in similar environments.

Amphitropical disjunctions in New World Menthinae: Three Pliocene dispersals to South America following late Miocene dispersal to North America from the Old World.

The subtribe Menthinae (Lamiaceae), with 35 genera and 750 species, is among the largest and most economically important subtribes within the mint family. Most genera of Menthinae are found exclusively in the New World, where the group has a virtually continuous distribution ranging from temperate North America to southern South America. In this study, we explored the presence, timing, and origin of amphitropical disjuncts within Menthinae. Our analyses were based on a data set consisting of 89 taxa and the nuclear ribosomal DNA markers ITS and ETS. Phylogenetic relationships were determined under maximum likelihood and Bayesian criteria, divergence times were estimated with the program BEAST, and ancestral range estimated with BioGeoBEARS. A North Atlantic Land Bridge migration event at about 10.6 Ma is inferred from western Eurasia to North America. New World Menthinae spread rapidly across North America, and then into Central and South America. Several of the large speciose genera are not monophyletic with nuclear rDNA, a finding mirrored with previous chloroplast DNA results. Three amphitropical disjunctions involving North and southern South America clades, one including a southeastern South American clade with several genera, were inferred to have occurred within the past 5 Myr. Although three New World Menthinae genera occur in both North and South America, none exhibit an amphitropical disjunction. However, three clades exhibit amphitropical disjunctions, all dating to the early Pliocene, and all involve jump dispersals to either southeastern or southwestern South America from southeastern North America.

Alseodaphnopsis: A new genus of Lauraceae based on molecular and morphological evidence.

An investigation of a questionable species of the genus Alseodaphne led to the discovery of a new genus Alseodaphnopsis H. W. Li & J. Li, gen. nov., separated from Alseodaphne Nees, and a new species Alseodaphnopsis ximengensis H. W. Li & J. Li, sp. nov., endemic to Yunnan province, China. This new species is characterized by having big, axillary, paniculate inflorescences, as well as large, subglobose fruits. Based on DNA sequence data from two gene regions (nuclear ribosomal ITS and LEAFY intron II), we investigate its phylogenetic position within the Persea group. Phylogenies using maximum parsimony (MP) and Bayesian inference (BI) support the recognition of Alseodaphnopsis as a distinct genus but do not resolve well its relationship within the Persea group. The new genus is circumscribed, eight new combinations for its species are made, and a description and illustration of the new species are provided.

Polyploidy as a Factor in the Evolution of the Bouteloua curtipendula Complex (Poaceae: Chloridoideae)

In this paper we assess the impact of polyploidy and hybridization in the Bouteloua curtipendula species complex (BCC). The BCC is a monophyletic group of perennial grasses in the Chloridoideae subfamily. We tested for evolutionary signatures of hybridization and polyploidy in the BCC by obtaining 77 chromosome counts from anther mother cells (2n = 20 to >100) and comparing the phylogenetic pattern of diploids and polyploids in nuclear and chloroplast trees. We sequenced ITS and trnT-L-F regions for 96 and 70 individuals, respectively, resulting in 150 nuclear ribosomal ITS sequences, including 54 cloned sequences. We found no evidence for recombination between ITS sequences with a PHI test. Maximum parsimony and Bayesian analyses were used to estimate the ITS phylogeny. Diploid samples were found in all clades, while most of the polyploid samples were concentrated in a single clade. Cloned diploids contained one to three copies of ITS with >99% sequence similarity. The tetraploids B. purpurea and some B. curtipendula samples had a low amount of variation among ITS copies, while the cloned polyploids possessed several highly divergent ITS copies. Pollen size correlates with ploidy-level in the BCC, but is not a clear indicator of genome size. We found evidence that the BCC lineage has a complicated evolutionary history that has included autopolyploidy and allopolyploidy.

Saxifraga kegangii (Saxifragaceae), a new species from Hunan province of central China

Saxifraga kegangii, a new species of Saxifraga sect. Irregulares (Saxifragaceae) from Hunan province of central China, is described and illustrated. This new species can be easily distinguished from related taxa by its leaf shape and disc semiannular around the side of the ovary. Placement of this species within Saxifraga sect. Irregulares is assessed based on molecular phylogenetic analysis of the nuclear ribosomal ITS and two chloroplast regions (trnL-F and psbA-trnH) sequences together with morphological comparisons.